1. Field of the Invention
The field of invention relates to sheave apparatus, and more particularly pertains to a new and improved tri-lobe sheave wherein the same is arranged to effect varying ratios and orientation of drive and driven belts between cooperating flanges of the sheave structure.
2. Description of the Prior Art
The centering and alignment of cooperating flanges relative to sheave structure has in the prior art been of a costly and complex construction. The instant invention attempts to overcome deficiencies of the prior art by providing for cooperating flanges in a sheave organization to effect spreading of the cooperating flanges to accommodate a drive belt therebetween in accordance to speed of the belt structure mounted within the sheave structure.
Prior art sheave apparatus has been set forth in U.S. Pat. No. 4,149,425 to Williams wherein an adjustable door flange sheave includes spring biased flanges cooperating relative to one another to accommodate variations of speed of a sheave structure.
U.S. Pat. No. 4,023,247 to Baer; U.S. Pat. No. 4,301,995 to Niskin., and U.S. Pat. No. 4,421,498 to Deleu, et al. are further examples of adjustable sheave structure of the prior art.
Accordingly, it may be appreciated that there continues to be a need for a new and improved tri-lobe sheave as set forth by the instant invention which addresses both the problems of ease of use as well as effectiveness in construction in maintaining the sheave apparatus in a fixed orientation relative to a shaft member directed coaxially therethrough and in this respect, the present invention substantially fulfills this need.